Machine for making concertina folds with reversible rollers and means for reversing same

ABSTRACT

A machine for folding strips of sheet material for example paper or cardboard or the like in a concertina-like manner. It comprises a plane member for the sliding of the strip of sheet material which is to be folded and a device suitable to prevent the returning of the strip. The device is arranged at the end of the plane member towards which the strip slides. It further comprises a pair of folding members consisting of a first roller means and a pair of second rollers parallel to and tangentially engaged with the first roller means. The second rollers are rotatably supported at the outlet of said non-returning device so as to lie above and below the strip respectively and cooperate with said first roller means so as to grip the strip alternately and form the folds. Inversion means are provided to drive the rollers alternately in opposite directions and photoelectric members are positioned to actuate the inversion means according to the position of the folded sheet material. Another photoelectric device detects the trailing end of the sheet and causes ejection of the folded sheet.

United States Patent 1 Roda [ MACHINE FOR MAKING CONCERTINA FOLDS WITH REVERSIBLE ROLLERS AND MEANS FOR REVERSING SAME [75] Inventor: Donato Roda, Bologna, Italy [73] Assignee: Faltex-Fllzmaschinentabrick AG,

Wohlen, Switzerland 221 Filed: July 12,1971

21 Appl.No.: 161,737

Primary EJtamirter- F. Barry Shay H Auam wernetw; 'Kleeniaii" 2a. Jzq, JJO.

[111 3,747,917 July 24, 1973 57 ABSTRACT A machine for folding strips of sheet material for example paper or cardboard or the like in a concertina-like manner. It comprises a plane member for the sliding of the strip of sheet material which is to be folded and a device suitable to prevent the returning of the strip. The device is arranged at the end of the plane member towards which the strip slides. It further comprises a pair of folding members consisting of a first roller means and a pair of second rollers parallel to and tangentially engaged with the first roller means. The second rollers are rotatably supported at the outlet of said non-returning device so as to lie above and below the strip respectively and cooperate with said first roller means so as to grip the strip alternately and form the folds. Inversion means are provided to drive the rollers alternately in opposite directions and photoelectric members are positioned to actuate the inversion means according to the position of the folded sheet material. Another photoelectric device detects the trailing end of the sheet and causes ejection of the folded sheet.

PAIENIEBM 3.147. 917

' SHEET 1 0F 2 INVENTOR Donoto RODA BY AGENT PATENTED M24975 SHEEI 2 [1F 2 INVENTOR Donoto RODA AGENT MACHINE FOR MAKING CONCERTINA FOLDS WITH REVERSIBLE ROLLERS AND MEANS FOR REVERSING SAME BACKGROUND OF THE INVENTION This invention relates to a machine for concertina folding, i.e., along transversal folds successively in one direction and the other, a strip of sheet material such as paper, cardboard and the like.

Conventional machines of this type are rather complex, costly and bulky.

Moreover the adjusting of conventional folding machines in order to obtain the required distances between successive folds in the strips is difficult.

SUMMARY OF THE INVENTION An object of the present invention is to obviate the aforementioned disadvantages.

The machine according to the present invention comprises a machine for concertina folding strips of sheet material, characterized in that it comprises a plane member on which the strip to be folded slides, non-return means including a device adapted to prevent the return of the strip and arranged at that extremity of the plane member toward which the strip slides, said device having an outlet, a pair of folding members consisting of a first roller means supported in front of the outlet of said device, said first roller means including a member with a surface movable across the path of said strip adjacent said outlet, and a pair of second rollers parallel to and tangentially engaged with said surface, said second rollers being rotatably supported at said outlet so as to lie above and below the plane member respectively and each co-operating with said first roller means so as to grip the strip elternately and form the folds, means including coupling means and inversion means for driving said rollers alternatively in opposite directions and with equal and opposite peripheral velocities at corresponding tangential points, and means including control members to control actuation of the coupling means and inversion means.

BRIEF DESCRIPTION OF DRAWINGS The features and advantages of the invention will become fully apparent from the detailed description given hereinafter of preferred but not limiting embodiments- DESCRIPTION OF THE PREFERRED EMBODIMENTS With reference to said figures, the machine comprises a plane member or feeding table I, on which a strip of sheet material 2 slides in the direction indicated by the arrow A. The strip unwinds from a feed reservoir 3, fixed upstream and below the feeding table 1. While sliding, one side of the strip 2 is guided by a side wall 4, which rises from one longitudinal side of the table 1.

At the downstream extremity of the table 1 a device which prevents the return of the strip, i.e., which prevents the strip from sliding in the direction opposite to the arrow A, is provided.

In figures 1a, lb and 10 this non-return device consists of a blade 5 transversal to the table 1 and pivoted at its back end to suitable supports whihch rise from the table. The front of the blade 5 closes on to the table 1 by gravity, forming a kind of pincer.

In FIG. 2a the non-return device consists of a roller 6, which rests transversally on the table 1. The roller 6 is pivoted eccentrically on suitable supports which rise from plane 1, in such a manner that its axis is in front of the axis of the fulcrum with respect to the direction of the arrow A.

A transversal blade 7 is placed after the roller 6 and is rigid with the table 1 and forms with said table a passage for the strip 2.

In FIG. 2b the non-return device consists of two idle rollers, 8a and 8b, which are placed transversally at the end of the table.

The roller 8b is tangential to the upper face of the table, whereas the upper roller 8a is closed by force on the roller 8b. The two rollers can rotate only in the direction of accompanyment of the strip 2, i.e., only in the direction A.

The rollers 8a and 8b may also be motor driven, as

will be more clearly explained hereinafter. Downstream from the two rollers 8a and 8b there is a pair of transversal blades 9, which at their inlet form an entry zone. One of the two blades is at the level of the table 1 and the other is parallel and above the former. A passage is thus defined between the two blades for the strip 2. Considering again FIGS. la, lb and 1c it can be seen that in front of the outlet of the blade 5 (at the exit of the blade 7 or of the blades 9 in the case of the non-return devices shown in FIGS. 20 and 2b) a roller 10 is placed transversally, which is parallel and tangential with two rollers 11a and 11b lying above and below the extremity of the table 1 respectively.

The rollers 11a and 11b have the same diameter and are rotatably mounted in supports, not shown, supported by the machine structure. The roller 10 is rotatably mounted in supports guided slidingly in suitable links provided by parts rigid with the machine structure. The links extend perpendicularly to the plane which passes through the axes of the rollers 11a and 11b, i.e., parallel with the dashed line i, and springs act on their supports in order to maintain the roller 10 engaged against the rollers 11 a and 11b. The rollers 11a and 11b are driven alternately in one common direction B (FIG. la) or in another common direction C (FIG. lb) and correspondingly the roller 10 is driven in the direction D or in the direction E. The various rollers are driven with uniform motion and consequently their peripheral velocities at the tangential points are equal. The rollers may be driven in any conventional manner, either manually or through gear transmission systems, or by belts and pulleys, or by connecting rod assemblies driven through coupling means by a selfbraking'and reversible motor. The alternate inversion of rotation of the rollers may be obtained in any conventional manner, either by limit switches for the motor or by paper-sensitive devices, adjustable according to the distances required between successive folds.

FIGS. 1a, 1b and 1c for example show two light source and photoelectric cell units 12a and 12b,

arranged upperly and lowerly respectively to the machine assembly. These units are disposed at predetermined distances from the tangential lines of the roller 10 with the rollers 11a and 11b respectively, in such a manner that the tangential planes of the rollers pass between the light source and photoelectric cell unit. The third light source and photoelectric cell unit 13 is mounted near the non-return device, with the light source on one side and the photoelectric cell on the other side with respect to the intermediate table 1. By way of a suitable hole in the table 1, the unit 13 controls the presence of the sstrip 2 on the table 1.

Referring to FIGS. la, 1b and 1c, the operation of the machine of the invention is the followingfWhen the strip 2 is thrust so that it enters the non-return device (5 or 6 or 8a8b), the unit 13, suitably connected in the electric circuit of the machine, emits a signal because of the presence of the strip and this causes the coupling of the motor which drives the rollers, for example so as to rotate the rollers 10 and Ila-11b in the directions B and D respectively (see FIG. la).

When the front portion 2a of the strip 2 is taken between the rollers 10 and 11a it rises upwards in the direction F, supported by suitable guides, not shown. When the front portion 2a reaches the unit 12a, this emits a signal which causes the inversion of the driving motor which now drives the rollers Ila-11b and 10 in the directions C and E respectively (see FIG. lb). The strip 2 on the table 1 stops and its front portion 2a, squeezed between the rollers 10 and 11a, descends in direction G so forming a loop 2b, which is seized between the rollers 10 and 11b, hence forming a first fold line. The strip 2 then slides in direction A and the portion 2a covers a second portion of the strip. When the fold line so formed arrives at the unit 12b there is a new inversion of direction of rotation of the rollers 11a 11b and 10 (i.e., the respective directions of rotation B and D are re-established).

The two portions of the strip rise and a new loop forms, giving rise to a new fold line, inverted with respect to the first. Thus a concertina pack 14 is gradually formed (see FIG. 1c which shows a stopped arrangement in which the rollers are just before an inversion of rotation). As can be seen the pack 14 is always held between the rollers l1a-l lb and 10.

Because of the thickness of the pack 14, the roller 10, thrust by the spring on to the rollers 11a and 11b, moves back slightly from them along the line i. When the rear end of the strip 2 passes beyond the unit 13, i.e., when the folding of the strip is complete, the rollers continue to rotate in the direction in which they are rotating, even when the pack 14 reaches one of the units 120 or 12b. In this manner the pack 14 is expelled from the machine, which thus terminates its operation.

The above described preferred embodiments of the present invention have been set out in detail for purposes of illustration only and it should be understood by those skilled in the art that numerous variations of these and other embodiments are feasable within the scope of the present invention. For example the rollers 11a, 11b and 10, may be replaced by roller sectors. All the rollers or part of them may also be replaced by flexible endless bands. Such an embodiment is illustrated in FIG. 3, where instead of the roller 10 a band 17 is provided wound on a pair of cylinders 15, 16 in such a manner as to lie with its surface tangential to the rollers 11a, 11b and therefore substantially perpendicular to the table 1. This embodiment is particularly advantageous in that the supports for the cylinders 15, 16 can be fixed, because the increase in thickness during the folding can be absorbed by the compliance of the band 17.

I claim:

1. A machine for concertina folding strips of sheet material characterized in that it comprises a plane member on which the strip to be folded slides, nonreturn means including a device adapted to prevent the return of the strip and arranged at that extremity of the plane member toward which the strip slides, said device having an outlet, a pair of folding members consisting of a first roller means supported in front of the outlet of said device, said first roller means including a member with a surface movable across the path of said strip adjacent said outlet and a pair of second rollers parallel to and tangentially engaged with said surface, said second rollers being rotatably supported at said outlet so as to lie above and below the plane member respectively and each co-operating with said first roller means so as to grip the strip alternately and form the folds, means including coupling means and inversion means for driving said rollers alternatively in opposite directions and with equal and opposite peripheral velocities at corresponding tangential points, and means including control members to control actuation of the coupling means and inversion means.

2. A machine as claimed in claim 1, wherein said first roller means includes an endlessly wound band provided on rotatable cylinders said surface being on said band and having a portion which extends perpendicular to said plane member and on which said second rollers engage.

3. A machine as claimed in claim 1, wherein said first roller means includes a cylinder rotatably mounted in supports which are slidingly guided in the machine, and wherein there are provided spring means acting on said supports to hold the surface of said cylinder in tangential engagement with said second rollers.

4. A machine as claimed in claim 1, wherein said control members comprise a photoelectric cell and light source unit disposed at the plane member to be activated by the strip in such a manner as to cause the coupling and de-coupling of the coupling means and photoelectric cell and light source units respectively disposed substantially at the tangential planes between said first roller means and said second rollers to be activated by that portion of strip which is folded, to actuate said inversion means.

i I i I I UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,747,917 Da ed July 24; 1973 lnventm-(s) Donato Roda It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Page 1, left-hand column, after paragraph [73] insert:

Priority July 14 1970 Italy 3488A/7O Signed and sealed t Iiie 30th (1553f July 197 (SEAL) Attest: I McCOY M. GIBSON, JR. C. MARSHALL DANN Attesting Officer Commissioner of Patents FORM PC4050 uscoMM-Dc some-P69 V ,5. GOVEFNHENT PRINTING OFFICE: 9'5 0-355-33 

1. A machine for concertina folding strips of sheet material characterized in that it comprises a plane member on which the strip to be folded slides, non-return means including a device adapted to prevent the return of the strip and arranged at that extremity of the plane member toward which the strip slides, said device having an outlet, a pair of folding members consisting of a first roller means supported in front of the outlet of said device, said first roller means including a member with a surface movable across the path of said strip adjacent said outlet and a pair of second rollers parallel to and tangentially engaged with said surface, said second rollers being rotatably supported at said outlet so as to lie above and below the plane member respectively and each co-operating with said first roller means so as to grip the strip alternately and form the folds, means including coupling means and inversion means for driving said rollers alternatively in opposite directions and with equal and opposite peripheral velocities at corresponding tangential points, and means including control members to control actuation of the coupling means and inversion means.
 2. A machine as claimed in claim 1, wherein said first roller means includes an endlessly wound band provided on rotatable cylinders said surface being on said band and having a portion which extends perpendicular to said plane member and on which said second rollers engage.
 3. A machine as claimed in claim 1, wherein said first roller means includes a cylinder rotatably mounted in supports which are slidingly guided in the machine, and wherein there are provided spring means acting on said supports to hold the surface of said cylinder in tangential engagement with said second rollers.
 4. A machine as claimed in claim 1, wherein said control members comprise a photoelectric cell and light source unit disposed at the plane member to be activated by the strip in such a manner as to cause the coupling and de-coupling of the coupling means and photoelectric cell and light source units respectively disposed substantially at the tangential planes between said first roller means and said second rollers to be activated by that portion of strip which is folded, to actuate said inversion means. 